Why Buy From Orion

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These scopes provide the best performance but may require more skill to master and appreciate. They have exceptionally fine optics and mechanics. Some are easy to use but are but on the large or heavy side. Some are intended for specialized uses. These scopes will appeal to the more technically inclined. Referring to the manual is highly recommended.

Orion Dobsonians have always been known for superb optical and mechanical quality, wonderful ease of use, and remarkably affordable prices. One other thing they - and almost all other Dobs on the market - have had in common: you pushed the telescope to your observing target by hand.

Until now. Orion has heralded another giant leap in Dobsonian evolution with the SkyQuest XTg series of fully motor driven GoTo Dobsonians. Now, pointing a Dob to even the most elusive of NGC curiosities is as easy as pushing a button or two on the XTg Dobsonian's illuminated GoTo hand controller. High-torque servo motors guided by two pairs of high-resolution encoders then slew the telescope right to your object of interest - any of over 42,000 objects in the GoTo controller's database. No more nudging the telescope tube continuously to keep the object from drifting out of the field of view, either. The XT12g automatically tracks the object's motion, keeping it centered in the eyepiece while you savor the view. What's more, the closed-loop electronics of the XT12g let you aim the telescope manually - or endure the accidental bump - without losing orientation for accurate, automated GoTo pointing!

The SkyQuest XT12g combines GoTo pointing convenience with large-aperture light-gathering and an amazingly affordable price. It features a 305mm (12") aperture, 1500mm focal-length parabolic mirror (f/4.9) made from low-thermal-expansion optical glass. Enhanced reflectivity (94%) aluminum mirror coatings yield bright, high-definition images. The 12" primary mirror is center-marked to make precise alignment of the optics (collimation) easier to achieve. The reflector telescope's open mirror cell design facilitates efficient cooling of the mirror to ambient temperature. To cool down the telescope optics even more quickly, the XT12g mirror cell features threaded holes that accept an optional cooling accelerator fan (sold separately).

The sturdy base of the XT12g GoTo Dobsonian comes with both altitude and azimuth motors pre-installed for fast and easy assembly. Once aligned, the fully motorized XT12g will locate, center, and track any of the more than 42,000 celestial objects within its computerized database. Closed-loop GoTo electronics allow manual aiming of the telescope without losing GoTo alignment so you can save power and observe efficiently.

Let the Orion SkyQuest XT12g take your family on a guided tour of the night sky.

The SkyQuest XT12g GoTo Dobsonian telescope's hand controller features a softly red-illuminated keypad which lets you select a celestial object to explore using a variety of intuitive menus, or you can use the Tour function to explore the best objects in the sky at any time of year. The time you'll save by not having to manually search for your targets or fuss with star charts will allow you to kick back, relax, and spend more time enjoying the magnificent views through the eyepiece.

The XT12g optical tube comes equipped with a smooth, dual-speed 2" Crayford focuser (with 1.25" adapter). The dual-speed, 11:1 fine-focus ratio makes it easy to obtain finely detailed views of any celestial denizen. Both 2" and 1.25" telescope eyepieces can be used, thanks to the included 1.25" step-down adapter. With its Crayford mechanism, focus adjustments are silky smooth and free of backlash, even when using heavier 2" oculars

Enjoy wide field views of the night sky with the included 28mm DeepView 2" eyepiece.

You'll love exploring deep sky delicacies with the SkyQuest XT12g and included 28mm DeepView eyepiece. Its 56° apparent field of view provides a nice, wide window of sky to explore. The telescope's large 12" aperture collects a ton of light for bright views in the 2" eyepiece. With multi-coated optics and long 20mm eye relief, the 28mm DeepView is a great eyepiece for comfortable observations of the night sky.

Use the 12.5mm Illuminated Reticle eyepiece for easy and accurate GoTo alignment.

The included 1.25" 12.5mm Plossl eyepiece features an internal crosshair reticle pattern that can be illuminated for easy visibility at night. Using this powerful eyepiece to precisely center alignment stars helps improve the accuracy of the XT10g GoTo system for optimized object location and motorized tracking. The LED-illuminated double crossline reticle features adjustable focus and brightness.

The XT12g telescope optical tube drops into the Dobsonian base on a dovetail trunnion and locks in place with a single hand knob. A simple two-star alignment is all it takes to orient the telescope to the sky for GoTo operation. Then let the fun begin! When you're ready to call it a night, just loosen the knob and lift the tube off the base for easy transport or storage. Handles on the Dobsonian base's front and side panels make it easy to lift and carry, whether you're going from car to field, or from house to backyard.

The Orion SkyQuest XT12g GoTo Dobsonian also includes an EZ Finder II reflex sight, eyepiece rack for one 2" and three 1.25" eyepieces, hand controller bracket, quick collimation cap, and a digital download insert for Starry Night SE astronomy software. The XT10g Dobsonian requires power from a 12-volt DC field battery or AC adapter, sold separately. A DC cable is included that has a car lighter style plug for connecting to your 12-volt DC power source, and a coaxial plug for the power jack on the Dobsonian base.

If you are an intermediate or advanced deep-sky hunter who wants a big-aperture telescope but not the high price tag, a Dobsonian is the way to go. And now, finally, you can have one that offers the convenience of motor driven accurate GoTo pointing - to anything in the heavens you'd like to see! Make your next telescope the Orion SkyQuest XT12g GoTo Dobsonian reflector!

Limited Warranty against defects in materials or workmanship for one year from date of purchase. This warranty is for the benefit of the original retail purchaser only. For complete warranty details contact us at 800-676-1343.

Warning

Please note this product was not designed or intended by the manufacturer for use by a child 12 years of age or younger.

User level

Level 1 Beginner - Suited for a wide range of uses, these telescopes are simple to operate and set up. Some initial assembly may be required. Very good optical and mechanical quality. Great for families, young people, and folks who don't want to mess with equipment but just want to take a look. Any of these scopes will show you countless lunar craters, Saturn's rings and a myriad of star clusters and nebulas! Referring to the manual is recommended.

Level 2 Intermediate - These scopes offer higher performance and more advanced features than Level 1: Beginner models. They typically take a bit longer to learn and need some set-up or adjustments. But anyone with the slightest technical bent will have no problem getting familiar with these models. Referring to the manual is recommended.

Level 3 Advanced - These scopes provide the best performance but may require more skill to master and appreciate. They have exceptionally fine optics and mechanics. Some are easy to use but are but on the large or heavy side. Some are intended for specialized uses. These scopes will appeal to the more technically inclined. Referring to the manual is highly recommended.

Level 4 Expert - Expert telescopes offer uncompromising optical and mechanical quality for the most demanding amateur astronomer. They may be technically involved or designed for specialized use, such as astrophotography or detailed deep sky observation. They carry a premium price, but are designed to provide the ultimate performance in the field. Referring to the manual is highly recommended.

Optical design

Reflector telescopes use a pair of large and small mirrors to direct incoming light to the eyepiece.
Refractor telescopes refract, or "bend" incoming light to a focus by means of an objective lens.
Cassegrain telescopes, such as Maksutov-Cassegrains, "fold" incoming light using two mirrors and a front "corrector" lens.

Optical diameter

For telescopes, the optical diameter (also known as aperture) is the size of a telescope's main light-collecting lens or primary mirror, measured in millimeters or inches. Telescopes with larger optical diameters collect more light, which leads to an increase in brightness and image resolution compared to smaller instruments.

For binoculars, the optical diameter (also known as objective lens diameter) is the size of each of the front-facing objective lenses of a binocular measured in millimeters. Binoculars with larger objective lenses collect more light, which increases image resolution and brightness. Binoculars with larger objective lenses are recommended for low light situations, and binoculars with at least 50mm or larger objective lenses are recommended for pleasing astronomical observations at night.

Focal length

The distance from the center of a curved mirror or lens at which parallel light rays converge to a single point. The focal length is an inherent specification of a mirror or lens and is one of the factors in determining resultant magnification for a telescope (along with the focal length of the eyepiece being used).

Focal ratio

The focal ratio of an optical system is the ratio of a telescope's focal length to its aperture. Short focal ratios (f/5, f/4.5) produce wide fields of view and small image scales, while long focal lengths produce narrower fields of views and larger image scales.

Optics type

Newtonian reflectors will have either a spherical shaped mirror, which is less expensive to produce, or a higher quality parabola, which does not result in spherical aberration. Cassegrain telescopes routinely use spheres in addition to other lenses in the optical path to correct for residual spherical aberration.
Refractors use a series of lenses to provide a clear image. Designs range from a standard air-spaced doublet (two lenses in a row) to exotic designs such as oil-spaced triplets and 4-element multi group lenses.

Glass material

Refractors use glass lenses to focus the light, and the glass material plays an important role in the quality of the resulting image. Standard achromatic refractors routinely use Crown and Flint for the two elements, but more expensive apochromatic refractors can use ED (extra low dispersion) glass for one or more of the lenses. Reflector mirrors are made from glass with different levels of thermal expansion. Standard mirrors are made from material such as Soda-Lime Plate glass and BK-7 glass. Glass with Pyrex or other low thermal expansion material will not change shape as dramatically during the cool-down period, resulting in more stable images during this period.

Resolving power

The theoretical resolving power of a telescope can be calculated with the following formula: Resolving power (in arc seconds) = 4.56 divided by aperture of telescope (in inches). In metric units, this is: Resolving power (in arc seconds) = 116 divided by aperture of telescope (in millimeters). Note that the formula is independent of the telescope type or model, and is based only upon the aperture of the telescope. So the larger the telescope's aperture, the more it is capable of resolving. This is important to keep in mind when observing astronomical objects which require high resolution for best viewing, such as planets and double stars. However, it is usually atmospheric seeing conditions (not the telescope) which limits the actual resolving power on a given night; rarely is resolution less than one arc-second possible from even the best viewing locations on Earth.

Lowest useful magnification

Lowest useful magnification is the power at which the exit pupil becomes 7mm in diameter. Powers below this can still be reached with the telescope to give wider fields of view, but the image no longer becomes brighter at a lower power. This is due to the fact that the exit pupil of the telescope (the beam of light exiting the eyepiece) is now larger than the average person's dark adapted pupil, and no more light can fit into the eye.

Highest useful magnification

The highest practical limit is different from the often used "highest theoretical magnification" specification. The "theoretical" limit generally is 50x the aperture of the scope in inches (2x the aperture in mm). So for example, an 80mm refractor is capable of 160x, and a 10" telescope is theoretically capable of 500x magnification.
But after approximately 300x, theory breaks down and real world problems take over. The atmosphere above us is constantly in motion, and it will distort the image seen through the telescope. This effect may not be noticeable at lower powers, but at higher powers the atmosphere will dramatically blur the object, reducing the quality of the image. On a good night (a night where the air above is steady and the stars aren't twinkling), the practical upper limit of a large telescope is 300x, even thought the theoretical limit may be much higher. This doesn't mean the scope will never be able to reach those higher "theoretical" powers - there will be that rare night where the atmosphere is perfectly still and the scope can be pushed past it's practical limit, but those nights will be few and far between.

Astro-imaging capability

The astro-photographic capability of the telescope is based on the style, stability, and accuracy of the mount and tripod. Telescopes on either very lightweight mounts or non tracking mounts (such as Dobsonians) are capable of only very short exposures such as lunar photographs. If a motor drive is attached to an equatorial mount, even a small lightweight mount is capable of capturing some planetary detail. Larger EQ mounts that utilize very precise tracking and excellent stability are capable of longer exposure deep-sky photography.

Motor drive compatibility

A motor drive automatically moves the telescope in right ascension at the same rate as the east-west drift of the stars so stars can be continuously tracked in the eyepiece without manual adjustment. Motor drives are usually equipped with a hand control that allows the telescope's tracking speed to be slightly increased or decreased, which is particularly critical when taking long-exposure astro-images.

Computerized compatibility

Some mounts are compatible with a motorized Go-To system for fully automated computer finding of objects in the night sky. Others mounts are compatible with computer finding systems which require the user to manually move the mount to the object's position as indicated by the computer finder.

Warranty

This warranty gives you specific legal rights. It is not intended to remove or restrict your other legal rights under applicable local consumer law; your state or national statutory consumer rights governing the sale of consumer goods remain fully applicable.

Orders received by 1pm Eastern Standard Time for in-stock item the same business day. Order received after noon will ship the next business day. When an item is not in-stock we will ship it as soon as it becomes available. Typically in-stock items will ship first and backordered items will follow as soon as they are available. You have the option in check out to request that your order ship complete, if you'd prefer.

A per-item shipping charge (in addition to the standard shipping and handling charge) applies to this product due to its size and weight. This charge varies based on the shipping method.

This product is available to ship Standard delivery within the 50 US states and US territories/protectorates address. Delivery is not available to APO/DPO/FPO addresses . Delivery is available to Canada.

A complete assortment of accessories for your telescope, the Orion Premium Telescope Accessory Kit comes with five Sirius eyepieces, a Shorty Barlow, and six filters for lunar and planetary observing, and a case. Everything you need, all in one kit!

Take a giant leap into the future of telescope control! Now you can wirelessly control your Orion GoTo telescope right from your Apple iPhone, iPad, or Android device. All you need is an Orion StarSeek astronomy app (sold separately) and this module!

Having trouble viewing details on the Moons surface? This neutral-density eyepiece filter reduces glare so you can see more detail and surface features. The 1.25" Orion 13% Transmission Moon Filter is especially useful with large aperture telescopes.

Would you like more contrast and less glare while viewing the moon and bright planets? The 2" Orion Variable Polarizing Telescope Filter reduces both and brings out details. And you can adjust the amount of light transmission for the perfect view.

This set of Orion Q70 telescope eyepieces will appeal to skywatchers looking for wide field views. Included are the 26mm, 32mm and 38mm eyepieces, all of which have a 70anddeg; apparent field and are multi-coated.

Speed up the cooling of your large reflector's optics with the Orion Cooling Accelerator Fan. This fan attaches to pretapped holes in the mirror cell and uses 8 D-cell batteries (not included) which allows it to run for up to 14 hours continuously.

Zoom eyepieces allow you to view an object at low power and then view it at at a higher power without having to switch between eyepieces. The 7.2-21.5mm Orion Zoom Telescope Eyepiece has fully multi-coated optics for clear, sharp images.

The 1.25" Deluxe Orion Stargazers Filter Set is a comprehensive 6 filter set for the best views of all types of celestial objects. Includes the SkyGlow Light Pollution Filter, Variable Polarizing Filter, and 4 Planetary filters.

This set of Orion Expanse telescope eyepieces is perfect for those that want huge views of the sky. Included are the 6mm, 9mm, 15mm, and 20mm telescope eyepieces. All are fully coated for bright high contrast images.

The Orion LensPen Mini Pro Cleaning Tool is specially designed to clean any lens surface. It has a retractable natural hair brush for large particles on one end and a flexible cleaning tip equipped with chamois pad for smudges on the other end.

Each Ultra-Wide Orion LHD telescope eyepiece features an 80-degree apparent field-of-view and lanthanum glass to eliminate color-fringing and chromatic aberrations for true-color, high-contrast views of the cosmos with exceptional clarity.

At Orion, we are committed to sharing our knowledge and passion for astronomy and astrophotography with the amateur astronomy community. Visit the Orion Community Center for in-depth information on telescopes, binoculars, and astrophotography. You can find astrophotography "how to" tips and share your best astronomy pictures here. Submit astronomy articles, events, & reviews, and even become a featured Orion customer!